From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Alexis" <alexis@tpys.com.ar>
Subject: Re: DNAT problem
Date: Sat, 29 May 2004 12:36:37 -0300
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Message-ID: <000701c44592$bb254460$0200000a@heretic>
References: <20040529172536.6df75cca.leslie.polzer@gmx.net>
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To: netfilter <netfilter@lists.netfilter.org>

i think it could be

- that the isp (if you're connecting to one isp trough ppp0) has a filter for
port 80 (it seems strange)

are you mangling some packets? what is the output for iptables -t mangle -L?



----- Original Message ----- 
From: "Patrick Leslie Polzer" <leslie.polzer@gmx.net>
To: <netfilter@lists.netfilter.org>
Sent: Saturday, May 29, 2004 12:25 PM
Subject: DNAT problem


>
> Hello again,
>
> a DNAT problem is coming up.
> My firewall setup (simplified for testing) is currently as follows:
>
>
> ### <snip> ###
>
> ##### FILTER table #####
> # policies
> $ipt -P FORWARD ACCEPT
> $ipt -P   INPUT ACCEPT
> $ipt -P  OUTPUT ACCEPT
>
> $ipt -F
> $ipt -F FORWARD
> $ipt -F   INPUT
> $ipt -F  OUTPUT
>
>
> ##### NAT table #####
> # flush chains
> $ipt -t nat -F  PREROUTING
> $ipt -t nat -F POSTROUTING
> $ipt -t nat -F      OUTPUT
>
> # masquerading on ppp0 and vortex
> $ipt -t nat -A POSTROUTING -o   ppp0 -j MASQUERADE
> $ipt -t nat -A POSTROUTING -o vortex -j MASQUERADE
>
> # dnat
> $ipt -t nat -A PREROUTING -i ppp0 -p tcp --dport 80 -j DNAT --to-destination
192.168.35.191:80
>
> ### </snip> ###
>
>
> The last line is working with
>
> --dport 8080
>
> but isn't with
>
> --dport 80
>
> What's going on there?
>
>
> Kind regards,
>
> Leslie
>
>